There are many different types of exercise equipment available to a user. A person will normally have some goal in mind as to which muscles he or she wishes to improve. The user will then choose the particular machine or apparatus accordingly. For example, barbells are used to strengthen the arms and upper torso. A leg press is effective for improving a user's leg muscles.
For a user wishing to improve the mid-body muscles of the lower back and abdomen, there are two primary types of devices for this purpose. These devices require the user to either perform a sit-up motion or a rowing motion.
Sit-up devices normally include one portion that restrains the user's ankles and another portion that supports the user's body in a supine position. These devices commonly are in the form of an elongated platform that has a "T"-shaped ankle securing member proximate one end. The end of the platform may be attached at any one of a number of vertically-spaced points to a vertically-oriented support.
The second form of machine for improving a user's mid-body muscles is typified by a rowing machine. In this type of device, the user sits atop a support (often horizontally movable) and pulls back with his or her arms and upper body against a resistance.